Risk Factors Update Summary

• Net losses increased from $69.1 million to $78.6 million, a significant rise of $9.5 million.
• Approval of ELEVIDYS (SRP-9001) for DMD treatment in June 2023. Interim Phase 3 results showed no significant benefit on primary endpoint but positive results on secondary endpoints.
• Accumulated deficit rose from $102 million to $181 million, a substantial increase of $79 million.
• Funding for operations extended from early 2025 to 2026, indicating an additional year of coverage.
• Addition of Pfizer Inc.'s PF-06939926 and Fordadistrogene movaparvovec in Phase 3 trial.
• Raised gross proceeds from IPO from $112.5 million to $122.9 million, a notable increase of $10.4 million.
• Cash and cash equivalents, and marketable securities decreased from $181 million to $110 million.
• Increase in full-time employees from 45 to 64 as of December 31, 2023.
• Net proceeds from ATM program and Follow-on Offering increased to $86.8 million, up from $76.9 million.
• Phase 2 clinical trials initiated for PGN-EDO51 and PGN-EDODM1, expanding clinical development efforts.
• Net proceeds of $86.8 million received from shares sold under ATM program and Follow-on Offering.
• Increase in NOL carryforwards from $254 million to $354 million as of December 31, 2023.
• Transition from first-to-invent to first-to-file patent application system outside the U.S.
• Development of gene editing treatments by Enzerna Biosciences and Design Therapeutics, Inc.